The National Hockey League (NHL) has been trying to increase goal scoring for the last decade or so. The following table gives a set of summary statistics from the 2012 -- 2013 and 2017 -- 2018 NHL seasons. Season Mean Standard Deviation Number of Teams 2012 -2013 127.387 13.137 31 2017 - 2018 240.2812 22.669 32 Assuming that all assumptions have been met, complete the following exercises: a. At the 5% signicance level do the data provide sufcient evidence that the average number of goals scored in the 2012 - 2013 season is less than the average number of goals scored in the 2017 - 2018 season? {8 marks) b. Compute a 90% condence interval for the difference between the average number of goals scored in the 2012 - 2013 season and the 2017 - 2018 season. (5 marks) c. Do the results of the hypothesis test and condence interval agree? Explain. (2 marks)